Field of the Invention
The present invention relates to sheet overlap devices or apparatus, and more particularly to sheet overlap devices for overlapping sheets such as hand towels wherein the overlapping can be accomplished at high speed with the use of vacuum pressure.
In accordance with the present invention, the transfer from one vacuum roll to the other is made at the same surface velocity so as to provide better register of the overlap and wherein there will be less likelihood of jamming occuring.
A primary object of the present invention is to provide a method and means for overlapping sheets such as hand towels wherein hand towels have a "Z" fold with approximately a 1/3 overlap.
A still further object of the present invention is to provide feed overlap devices which in one form of the invention may utilize a horizontal discharge, whereas in a different or alternative arrangement, a vertical rather than a horizontal discharge of the machine is utilized so that there is an advantage to gravity helping the discharge from the folding rolls.
Still another object of the present invention is to provide a sheet overlap method and means which is especially suitable for overlapping hand towels at high speed wherein the lap roll utilizes multiple vacuum holds which pick the towel off of the bed roll and transfer it around to top strippers. Slugs in valves determine the cut-off point of the vacuum holes and the slugs are set to cut off the vacuum as the sheet is stripped from the lap roll. At a predetermined time, vacuum holes in the tail roll pull the back edge of the towel down onto the bottom guide so as to allow the leading edge of the next towel to slide over the top of the tail edge of the towel preceding.
A still further object of the present invention is to provide a method and means for overlapping sheets and in particular for overlapping hand towels wherein the apparatus is ruggedly constructed and efficient to use and which is relatively simple and inexpensive to operate.
Still another object of the present invention is to provide a sheet overlapping apparatus and method that has improved characteristics and advantages as compared to previous sheet overlapping arrangements.
Other objects and advantages of the present invention will become apparent in the following specification when considered in the light of the attached drawings.